Which of the following is not a valid C++ identifier?

In memory, an array of String objects __________.

a. consists of elements, each of which is a reference to a String object b. is compressed to four bytes for each element c. must be initialized when the array is declared d. consists of an array of references to String objects

In Windows, what is the term to define any blank area in a window?

A. input space B. white space C. open space D. unused space